Subject: General Aptitude · Chapter: Volume and Surface Area · Exam: · Marks: · Difficulty:
Water flows at the rate of 10 metres per minute from a cylindrical pipe 5 mm in diameter. How long will it take to fill up a conical vessel whose diameter at the base is 40 cm and depth 24 cm?
(a)48 min. 15 sec.
(b)51 min. 12 sec.
(c)52 min. 1 sec.
(d)55 min.
Answer
Answer (as printed): B
Explanation
Volume flown in conical vessel $=\frac{1}{3} \pi \times(20)^{2} \times 24=3200 \pi$. Volume flown in 1 min. $=\left(\pi \times \frac{2.5}{10} \times \frac{2.5}{10} \times 1000\right)=62.5 \pi$. $$\text { ∴ } \text { Time taken }=\left(\frac{3200 \pi}{62.5 \pi}\right)=51 \mathrm{min} .12 \mathrm{sec} .$$